WASHINGTON -LRB- CNN -RRB- -- Angelina Jolie was on a stage Thursday but was n't performing . Instead , she paid tribute to the millions of uprooted people across the globe made homeless by war .

Angelina Jolie said that sheltering countries can learn from the way refugees survive their difficulties .

A U.N. goodwill ambassador , Jolie was in Washington to observe World Refugee Day , an annual event that falls on Saturday this year . The poignant ceremony was sponsored by the United Nations refugee agency .

Tears flowed as refugees and displaced people shared their harrowing experiences and advocates related what they 'd seen in refugee camps .

`` I believe we must persuade the world that refugees must not be simply viewed as a burden , '' she said . `` They are the survivors . And they can bring those qualities to the service of their communities and the countries that shelter them . ''

Jolie spoke of her visits to refugee camps in Tanzania and Pakistan .

She met a boy about 15 years old in a Tanzanian refugee camp who , without a wheelchair , had to crawl since a shot in the back paralyzed him . His family was killed , leaving him as an orphan . Yet when he spoke with her , he did it with a smile .

`` He had this really remarkable , unbreakable spirit , '' she told CNN 's Anderson Cooper after the event at the National Geographic Museum .

`` I think of him and I ca n't complain about anything ... he was grateful and he had nothing and suffered everything . ''

The boy died a few months after she met him , Jolie said .

According to a U.N. High Commissioner for Refugees survey of displacement trends in 2008 , there are 42 million uprooted people -- 15.2 million were refugees , 26 million were internally displaced people and 827,000 were asylum seekers .

Afghans and Iraqis constituted almost half of all refugees worldwide . One out of four refugees was from Afghanistan , and 69 countries accepted Afghan refugees for asylum , agency officials found .

Jolie recounted her meeting with a pregnant Afghan refugee .

She lived in a small , roofless dirt house in an abandoned refugee camp in Pakistan and could not leave with the others because she was too far along in her pregnancy .

Pakistan struggles with the largest refugee population in the world , about 1.8 million , according to the United Nations . The country also has more than 2 million internally displaced citizens , largely because of the fighting between the Pakistani military and the Taliban since April .

Antonio Guterres , head of the U.N. 's refugee agency , elaborated on the plight of displaced people at the event .

He said internally displaced people `` face the same plight -LSB- as refugees -RSB- . They have lost the same as refugees . They do n't have the same international protections granted to refugees . ''

Conflicts like those in Pakistan , Sri Lanka and Somalia have caused more people to flee their homes , though the number of displaced people declined by about 700,000 in 2008 , the report said .

Recent fighting in the eastern Democratic Republic of the Congo and in Somalia last year brought total displacement in each to 1.5 million and 1.3 million , respectively . More than 2 million internally displaced people were in Sudan 's Darfur region , according to the report .

When a genocide targeting Tutsis in Rwanda in 1994 later spilled over into the Democratic Republic of the Congo , Rose Mapendo , a Tutsi , was caught in the middle . She spoke at the event and described her ordeal .

Mapendo , her husband and seven children were thrown into a death camp , where her husband was executed and her children starved , she said through tears .

While at the prison , she learned that she was pregnant . She gave birth in silence , on a concrete floor , Mapendo said . To her surprise , she had twins , and to her captors ' surprise , she named her newborns after them . Soon after her gesture toward the prison commanders , her family was freed after their 16-month ordeal .

Mapendo , named a CNN Hero in October , created Mapendo International , a nonprofit dedicated to identifying , saving and resettling endangered refugees . She was named humanitarian of the year at the event by the U.N. agency .

`` I want to encourage the refugees do n't give up , '' she said . Giving up `` is not an option . ''

CNN 's Khadijah Rentas , Shalina Wadhwani and Paul Courson contributed to this report

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Actress , U.N. goodwill ambassador spoke of visits to Tanzania , Pakistan camps

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Chief of U.N. refugee agency elaborated on the plight of displaced people

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Conflicts in Pakistan , Sri Lanka , Somalia have caused people to flee their homes

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Tutsi described her ordeal amid slaughter in Democratic Republic of Congo